He now adds to his labors the manufacturing of leather, from all kinds of hides, with the chemistry of fine tanning, which is equal to all previous mental motions. Add and you find 4250 revolutions all drawing on his brain each minute of the day. Add to this mental strain the increased action of his body which has to perform these duties and you see the beginning of a worry of both mind and body, to which you add manufacturing of engines, iron puddling, rolling, etc.; a delegate to a national convention, thoughts of the death of a near relative; add to this a security debt to meet during a money panic. By this time the mind begins to fag below the power of resistance. HEMIPLEGIA. Duration of such great mental vibrations for so long stops nutrition of all or one-half of the brain, and we have a case of "Hemiplegia," or the wheels of one-half of the brain run so fast as to overcome some fountain of nerve force and explode some cerebral artery in the brain and deposit a clot of blood at some motor supply or plexus. Thus we see men from over mental action fall in our National councils, courts, manufactories, churches, and almost all places of great mental activity. Slaves and savages seldom fall victims to paralysis of any kind, but escape all such, for they know nothing of the strains of mind and hurried nutrition. They eat and rest, live long and happy. The idea of riches never bothers their slumbers. Physical injuries may and often do wound motor, sensory and nutrient centers of brain; but the effect is just the same, partial or complete suspension of the motor and sensory systems. If you burst a boiler by high pressure or otherwise, your engine ceases to move. And just the same of an over-worked brain or body. Hemiplegia. "The half" and "I strike." Paralysis of one half of the body.[2] [Footnote 2: Chambers.] Hemiplegia is usually the result of a cerebral hemorrhage or embolism. It sometimes occurs suddenly without other marked symptoms, but commonly it is ushered in by an apoplectic attack and on return of consciousness it is observed that one side of the body is paralyzed, the paralysis being often profound in the beginning, and disappearing to a greater or less extent at a later period. Hemiplegia is much more rarely produced by a tumor. It then generally comes on slowly, the paralysis gradually increasing as the neoplasm encroaches more and more upon the motor tracks, though the tumor may be complicated by the occurrence of a hemorrhage and a sudden hemiplegia. A gradual hemiplegia may also be produced by an abcess or chronic softening of the brain substance. Other conditions or symptoms presented, will in such case, assist us to diagnose the nature of the lesion. CHAPTER IV. EAR WAX AND ITS USES.